In Beijing, a total of 1,055 injuries were reported among 10,977 athletes, equivalent to an incidence of 9.6 injuries per 100 registered athletes [3]. Among the 2,567 registered athletes (1,045 females, 1,522 males) in Vancouver, a total of 287 injuries were reported resulting in an injury rate of 11.3 injuries per 100 registered athletes [2]. On average 10–11 % of the registered athletes sustained at least one injury. In total, 10,568 athletes took part in the London Olympic Games [4]. Of these, 4,676 were female (44 %) and 5,892 male (56 %). Among these athletes, we recorded a total of 1,361 injuries, equalling an overall injury rate of 12.9 injuries per 100 registered athletes. On average, 11 % of the athletes sustained at least one injury (n = 1,190). There were 114, 18, and 7 athletes with 2, 3, and 4 injuries, respectively (Table 2.2).

The incidence of injuries varied substantially among the different sports in all three Olympic Games. In relation to the number of registered summer sport athletes, the risk of sustaining an injury was highest for football, taekwondo, field hockey, handball, weightlifting, and boxing in Beijing (all ≥15 % of the athletes) [3]. In comparison, the relative risk of an athlete to be injured in the London Games was highest in taekwondo, football, BMX, handball, mountain bike, hockey, weightlifting, athletics, and badminton (15–39 % of registered athletes were affected in each sport) [4]. The relative injury risk was lowest for archery, canoe slalom and sprint, track cycling, rowing, shooting, and equestrian (less than 5 % of the athletes were injured) (Table 2.2). The injury risk in female (13.3 injuries per 100 athletes [95 % CI 12.2–14.3]) and male (12.1 [11.2–13.0], RR = 1.10 [0.97–1.22], P = 0.11) athletes was similar. Nonetheless, male athletes were at significantly higher risk of injury in taekwondo (RR = 1.9; 1.1–3.5, P = 0.03), whereas females were at higher risk of injury in football (RR = 1.7; 1.2–2.2, P < 0.001).

In the Winter Games in Vancouver, injury risk was highest for bobsleigh, ice hockey, short track, alpine, and freestyle and snowboard cross (15–35 % of registered athletes were affected in each sport) [2]. Every fifth female athlete was injured in bobsleigh, ice hockey, snowboard cross, and freestyle cross and aerials, while the highest-risk sports for male winter sport athletes were short track (28 % of registered male athletes), bobsleigh (17 %), and ice hockey (16 %).

In Beijing, the distribution of injuries was as followed: about half of the diagnoses (n = 600; 54 %) affected the lower extremity, 20 % were related to the upper extremity (n = 218), 13 % to the trunk (n = 149), and 12 % to the head/neck (n = 133). The thigh (13 %) and knee (12 %) were most commonly injured, followed by the lower leg, ankle, and head injuries (9 %), mainly diagnosed as skin lesions or contusions [3]. Similar results were found in the London Games (Table 2.3) [4].

In Vancouver, for both genders, the face, head, and cervical spine (female 20 %, male 21 %) and knee (female 16 %, male 11 %) were the most prominent injury locations, followed for females by wrist (8 %) and for male athletes by thigh (10 %). Contusions (female 32 %, male 26 %), ligament sprains (female 20 %, male 11 %), and muscular strains (female 8 %, male 16 %) were the most common injury types. In alpine, freestyle, and snowboarding, 22 out of 102 injuries (22 %) affected the head/cervical spine and one fourth of all injuries the knee (24 %). Twenty concussions were reported, affecting 7 % of the registered athletes. These athletes participated in the snowboard (boarder cross and half pipe) and freestyle disciplines (ski cross and aerials), in bobsleigh, in short track, in alpine skiing, and in ice hockey. A catastrophic injury with death as outcome occurred in luge [2].

In Beijing, one third of the injuries (n = 282; 33 %) were caused by contact with another athlete. Noncontact trauma (n = 172; 20 %) and overuse either with gradual (n = 78; 9 %) or sudden onset (n = 110; 13 %) were also frequent causes of injury [3]. Similar results were found in the London Games [4]. In Vancouver, the three most common reported injury mechanisms were a noncontact trauma (n = 57, 23 %), contact with a stagnant object (n = 54, 22 %), and contact with another athlete (n = 36, 15 %) [2].

While 73 % of the injuries in Beijing occurred in the competition [3], injuries in Vancouver were evenly distributed between official training (54 %) and competition (46 %) (P = .18) [2], similar to the 2012 London Games [4]. However, in Vancouver, a specifically high proportion of training injuries was found for the three snowboard disciplines, freestyle cross skiing, short track, figure skating, skeleton, and biathlon. In these sports, three out of four injuries occurred outside of the competition (Table 2.3) [2].